1. Field of the Invention
The present invention relates to an elongated member made entirely or partially of extruded plastic, and suitable for the upper surface of decks, docks, or bench type seating, and for other uses, generally in walking, standing, or sitting areas.
2. Prior Art
There have been various prior proposals for using plastic extrusions for decking and like flooring needs, especially for outdoor use, for example as described in the following patents:
Canadian Patent No. 989,134, issued May 18, 1976 to Hassman; PA1 Canadian Patent No. 1,190,717, issued Jul. 23, 1985, to Stanley et al.; PA1 Canadian Patent Application No. 2,100,986, published Jan. 22, 1995, of Steadman; and PA1 Canadian Patent Application No. 2,108,425, published Apr. 15, 1995, of Bayly.
Also, U.S. Pat. No. 5,070,664, which issued Dec. 10, 1991 to Groh. et al., describes an extruded plastic structure for fitting onto wooden or steel benches to improve comfort and weather resistance.
The Canadian patents of Hassman and Stanley et al., and the Steadman application, describe structures formed of polyester resin or like material with glass fiber reinforcement, these structures being formed by pultrusion. The Bayly application describes a plastic channel type member, which seemingly might be extruded, although this does not appear to be mentioned.
A common drawback of plastic surfaces for decks and other walking areas is that these tend to be slippery, especially when wet. Some of these prior patents show ribs or other formations intended to provide a non-slip surface. Thus the structure shown in the Hassman patent has ribs on its upper surface, integrally formed of the same reinforced plastic material, and intended to prevent slipping. The Stanley et al. patent describes a non-skid feature provided by a grit surface applied to the upper face of the member during the pultrusion process. The Bayly application states that its flooring members can have textured surfaces so they will not be slippery when wet, although the nature of these surfaces is not given. The Groh et al. patent shows a structure with an overlying cap or "capstock" of between 15 and 25 mils in thickness, formed of a rigid vinyl resin, intended to improve weatherability, and which also has spaced apart, integrally formed, parallel ridges which provide a gripping surface.
These prior art non-skid features are believed to have some drawbacks. Thus, ribs of the type shown in the Hassman or Groh et al. patents provide little gripping effect in directions parallel to the ribs. In each case, the ribs are formed integrally with the surrounding material and thus have the same hardness or firmness. The actual decking made in accordance with the Groh et al. patent, including the ribs, has a hard surface and lacks friction in the direction of the ribs; tests discussed below give a comparison of the friction achieved with Groh et al. compared to material made in accordance with this invention. Surfaces of the kind described in the Stanley et al patent, or in the Bayly application, are likely to be difficult to produce as part of an extrusion process. There exists a need for a flooring member which can easily be produced by extrusion, and which has a non-skid feature which is effective lengthwise of the member and not only in the cross direction.